Dan the man
Well-Known Member
Excuse me, my bad
318 with Edelbrok perfomer intake and 600 cfm 4 barrel, what headers please?
- Thread starter Peter Z
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If you decide on headers stick to 1 5/8 size on your
combo.
combo.
Dan the man
Well-Known Member
I have a question about header tube diameter. Is it true that the 1 1/2" primary tube size is better for the scavenging of the cylinders as the smaller tube size will remove the exhaust gases faster and more complete? From the reading I've done this is supposed to be true in engines up to 360 cid and less 500 horsepower. I don't know this as fact only from what I've read and you know how articles can be miss leading. So I thought that I would ask someone who has the experience and knowledge about these things.
OK, by by. You’ll get over it.Well being called a "lier" whatever that is, justifies me putting you on ignore a while back.
LMAO
No. I don’t know where you read that but not all articles are actually factual. 1 case in point I was reading some guy said you don’t want more than a 200cc runner on your 440, ever.
Yea! We know this guy don’t know a freakin thing!
As suggested earlier, a 1-5/8 tube header will carry a 318 from stock to pretty potent. I wouldn’t suggest a 1-3/4 header for a stock 360 & not until it starts making some good power.
Too large of a header affects power, mostly down low. Where you want the power of the engines torque the most.
@273 often likes to post magazine articles. There was a header test done showing just this. Perhaps he will post it.
Newbomb Turk
Well-Known Member
No. There isn’t a decent V8 I can think of that would want a 1.5 inch tube.
You need to drag your *** to a dragstrip and see how many cars have 1 1/2 inch headers on them.
The answer is NONE. And disabuse yourself of the notion that a street car would want something different.
Dan the man
Well-Known Member
I was only going by what I've read and I know that you can't believe everything you read in those books
Newbomb Turk
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junkyardhero
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does anybody even sell 1.5" primary tube headers for our cars?
anyway, to the question at hand. 1 5/8 and call it done. best fit chassis and motor wise, broadest selection of mfgrs
anyway, to the question at hand. 1 5/8 and call it done. best fit chassis and motor wise, broadest selection of mfgrs
junkyardhero
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knowing matt, they're custom made and tuned precisely to his cam, valves and intake tact. ;)
Dan the man
Well-Known Member
I was talking about street cars. I'm not saying that it's correct but look how good those 5.0 mustang's ran and they have 1 1/2" primary tube headers. What's a pain in the butt is why these magazines print information that can be miss leading
Brian Slowe made them. You know I have Pipemax and went as close to Elston's suggestions as we could. I have a few extra flange plates for future projects or if someone else wants because Brian wasn't comfortable getting into blacksmithing the tubes into the flange. Not going into more here because its way off from what the OP is looking to get into. There's a thread about it on Speed-talk.
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I can't recall if the old early A-Body Dougs were 1.5 off the head. Mapes has them on his Goldfish. Those were something like three sections on one side.
That's the only off-the shelf ones that come to mind.
1 5/8 is far more common that's for sure.
Newbomb Turk
Well-Known Member
There was a test years and years ago. I got the story from a guy that was there. Take it for what it’s worth.
He was down in California and this guy was at a track testing. A car magazine group showed up to test…you guessed it…headers.
It was some 283 Chevy and I forget the car. Anyway, they had 3 sets of headers. 1.5, 1.625 and 1.750 inches.
They flogged that thing all day and guess what??? The 1.750 inch headers were the quickest and fastest. It wasn’t even close.
But guess what the article said when the test was published? It wasn’t that the 1.750 inch header was quickest and fastest, but the 1.625 header gave the best all around “feel”.
What a bunch of horse **** but that’s what happens. And just because someone does some testing, it doesn’t mean they did it correctly.
I can’t tell you how many times I’ve went to the track with guys and they struggled to do a burnout the same twice on a row. Let alone hit two or even one shifts the same.
I will say you can use a smaller tube header IF your compression is high enough. A 14:1 engine won’t need as big a header tube as a 11:1 engine. Compression ratio matters.
Also IF you follow Calvin Elston to the letter you can use a smaller tube header. I agree with him most exhaust ports and valves are way too big.
So you’d need to shrink the port and valves, make the exhaust port smaller. And then stuff the biggest intake valve you can fit
Then you have to change your cam timing to match.
Michael Harrington
Well-Known Member
The hobby is all about tinkering. Often things are purchased and installed that don't improve acceleration but are part of the hobby. Think engine dress up kits- yellow spark plug wires and those big Accell super coils back in the day. Yes, those parts were legit performance parts but most installed them for fun and they really experienced no gain in performance- it was fun to do even on a car that ran high 14s. If one does not have the spare $$ for headers then run the iron manifolds with a dual exhaust and don't look back. If one eventually wants headers in their SB A body one could buy some Summit or Flowtech brand headers and install on a day off- just know those low hanging tubes can be a real downer for some. I myself if in this scenario would save for a set of raw unpainted Dougs headers. But with headers -even TTI and Doug don't expect a huge seat of the pant's noticeable improvement in such a mild engine- the hobby is about tinkering and yes- that means money is spent on items that yield no significant improvement. My 1995 Dakota hot rod project will stay with manifolds because there are no long tube headers made for this platform anymore. Hooker used to make a set but they were almost $800 uncoated and now that they are discontinued the used and NOS prices are $$$$$$. No thanks. There is a run of TTI manufactured long tubes available but not for my generation of Dakota. Those are a work or art and if they were available for my gen truck, I would pony up the $$$ (over $1100) for a set only because of their high-quality heavy-duty construction. But its a moot point cuz they won't work for me. Manifolds it is for me.
Many thanks to everyone for the contribution and info. I can see that there is other things I can do before I get to the headers. I am not chasing seconds, what I am after is a grin on my face every time I take the old girl out. All about feelings for me and for that she has plenty of charm in her as is. I will sort out the stands first, and then in the future go with the cam and headers. Thanks
Uncle Bob
Shiny paint causes stress.
Doug's are cool and all but I've got a brand new set off right now to ding them in a few places - hits power steering and the torsion bar. Actually I should say they lay right up against the power steering and torsion bars. Close, but no cigar.
Anyway don't confuse yourself thinking it's a straight-across swap from manifolds to headers. And don't forget the pain if/when you snap a stud off in the head removing the factory parts.
Anyway don't confuse yourself thinking it's a straight-across swap from manifolds to headers. And don't forget the pain if/when you snap a stud off in the head removing the factory parts.
furrystump
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318’s are kinda their own special animal that a number of people have “been there, done that” on what the low hanging fruit would be. I personally would put exhaust manifolds down the list some. This just comes from my personal experience running 340 manifolds. Not the same animal, but under estimated just the same.
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